The manufacturing of recombinant coagulation factor VIII is a complex, labor and capital intensive endeavor. Of the recombinant proteins currently marketed, coagulation factor VIII is manufactured with the lowest efficiency and is by far the most expensive on a per unit mass basis with a pharmacy price of $10,000,000 per gram. The goal of the current application is to develop a product technology and a manufacturing process that can improve the production volume and pharmacy price of factor VIII biologics. Expression Therapeutics has developed two technologies, a bioengineered factor VIII transgene that demonstrates 100-fold greater expression than standard human factor VIII, and a new baby hamster kidney-derived (BHK) cell line, designated BHK-MS, that can be cultured and expanded indefinitely and at high density in serum and blood product-free medium under suspension bioreactor conditions. In the current application, we propose to optimize the fermentation and purification processes and conduct a scaled up production run that will demonstrate proof of concept of the manufacturing process and generate a substantial supply of bulk drug substance qualified for subsequent preclinical safety, efficacy and stability testing necessary to submit an Investigational New Drug application during phase II of the SBIR mechanism.